CHAP. XIIL] ABOUT FUNGI. 181 



subjecting it to an experiment. Examined by the 

 microscope, we note the absence of any green or red 

 colouring matter. It has no chlorophyll. If we run 

 in a little solution of iodine on the slide we shall 

 observe that the protoplasm is stained brown ; the 

 cell-wall remains uncoloured. If starch were present 

 it would be stained blue. Torula, therefore, has no 

 starch, and this absence of starch is a characteristic 

 of fungi. 



If we place the slightest particle of yeast in a sac- 

 charine solution, we shall observe that the liquid* 

 previously clear, has in a day or two become turbid. 

 If we take up a small quantity of the liquid on the 

 point of a pencil or a glass rod, and place it under the 

 microscope, we shall find that the whole of the fluid 

 is teeming with millions of Torul(E> which have been 

 produced by the multiplication of the few we added 

 to our liquid. We now take two bottles and half fill 

 them with fresh saccharine fluid, then add the slightest 

 drop of the turbid liquor to each, cork them both up, 

 and place one in complete darkness, the other in the 

 light. On examining them in a few days, we shall 

 find that they are equally turbid. Therefore Tomla 

 is not dependent upon light for the power of growth ; 

 this also is a characteristic of fungi. On loosening 

 the cork after a day or two, we shall notice a terrific 

 rush of air or gas from the bottle, or if we fail to 

 loosen or remove the cork the pressure from within 

 will do it for us with considerable vehemence. But 

 we can test this gas, and shall then find it to be car- 

 bonic anhydride, which is the same as the gas exhaled 

 by animals. Here we have another characteristic of 



